Answer:
Step-by-step explanation:
Force of gravity = GMm/r^2 = ma
a being the acceleration due to gravity at some distance r from the center of the Earth. I'll use 6400 km for the radius of the Earth so r = 6734 km or 6734000 meters
a = GM/r^2
plugging in G = 6.67 x 10^-11
M is the mass of the Earth = 6 x 10^24
and r is from above
a = 8.825 m/s^2 = 0.9g
so 90% the acceleration of gravity on the surface.